5G use by consumer electronics has definite and (in my opinion) founded concern for aircraft avionics, to an extent. I'll preface this by saying these concerns have been raised and government authorities are seemingly dealing with it so as to avoid any major incidents or disruptions.

The inside scoop that I can give you is this.

5G stands for 5 gigahertz Fifth Generation (EDIT: as some commenters pointed out, I was originally wrong here. 5G stands for "Fifth Generation" and has nothing to do with the frequency range it operate in), and is simply the frequency of which the wireless signals arrive to your cell phone. 5G operates in the frequency band of 3.65-3.98GHz. Frequency in its most basic form is energy pulses, with a higher frequency having those energy pulses closer together (higher energy per time period) and a lower frequency having them farther apart (lower energy). Everything in wireless transmission uses frequency (generally), including GPS, radio navigation, and communication radio.

Now communication radio uses the range 117.975MHz (which stands for megahertz) and 137.00MHz (although the radios are tunable only to 118.00MHz and 136.975MHz, there is a buffer for this bandwidth). This means it is physically impossible for 5G to interfere with any voice communication, as the waves are so so so much different than the range which our radios are built and designed to pick up.

Now as for avionics equipment... most of our stuff is built to operate at vastly different frequencies than anything your cell phone uses, but there is one piece of tech that uses a band very close to 5G. That is the radio altimeter, as I mentioned in a comment above and also in this comment here. Radio altimeter uses the frequencies of 4.2GHz to 4.4GHz, which is less than half a GHz above from cell phone 5G towers. Also, due to the design and construction of this device, it requires utmost precision and signals that are as clean as they can possibly be. This piece of equipment is also very important for low visibility landings (at night or in weather) and is also the main method by which helicopters can autohover at a fixed altitude. All this to say; its very important that it works without interference. Cell towers are extremely high power transmitters, so the concern for these two pieces of equipment conflicting was certainly valid.

Now outside of some headaches and nasty emails between government transport authorities and telecomm companies, what does it mean for you? Well the long and the short of it is you are very, very, very unlikely to ever notice. Telecomm companies don't like building tall cell towers near airports for obvious reasons, and due to the nature of 5G it can be adjusted to be quite precise in where the waves end up. Canada and the US have already introduced mandates for 5G cell tower placement (you can read the CASA that Transport Canada put out here) and it seems that there is no official concern following these.